After the murder of his brother Frank, Al Capone is out for revenge against William Dever and the Chicago police. He plots to kill every undercover cop that was in Cicero on the day of Frank’s death. Before he can set his plan in motion, however, Johnny Torrio returns from Italy and reclaims his control of their criminal empire. Torrio forbids Capone from killing cops, fearing it would spark an all-out war.
Despite Capone’s personal loss, Torrio returns to a booming business that’s raking in $10 million a month. However, as Torrio and Capone’s empire grows, it becomes harder to keep smaller factions under control.
After a small group of Italian mobsters attacks one of Dean O’Banion’s distilleries, O’Banion blames Torrio and decides to end their business partnership. He announces his retirement to Torrio and offers Torrio an opportunity to buy him out. Torrio meets O’Banion at the Seine Brewery on May 19, 1924, with the buyout money. Chicago police raid the brewery and arrest Torrio while letting O’Banion walk free: O’Banion had set the whole thing up.
With prior convictions, Torrio serves a mandatory prison sentence but is first released on bail. He vows to kill O’Banion as payback and gives Capone his blessing to kill O’Banion. Capone spends months planning the hit. Capone knows that catching O’Banion off guard is nearly impossible, so he places an order with O’Banion’s flower shop for nearly $20,000 worth of flowers, knowing that O’Banion personally oversees his biggest arrangements.
On November 10, 1924, O’Banion works in his shop preparing the flower delivery. Two of Capone’s men enter the shop and fatally gun O’Banion down. Four days later, Chicago’s most powerful Irish gangster is laid to rest in one of the most lavish funerals Chicago has ever seen. More than two dozen cars are required to transport floral arrangements as a crowd of 10,000 mourns the death of the infamous gangster. Torrio and Capone attend the funeral, infuriating O’Banion’s top lieutenants, Hymie Weiss and Bugs Moran.
After the funeral, Weiss takes control over what’s left of O’Banion’s empire. Before he can take revenge on Torrio and Capone, he knows he must defend his turf against other rival gangs who think O’Banion’s death means it’s open season on the Irish gang’s territory.
Chaos breaks out as smaller gangs through the city begin a turf war. It’s the beginning of an era of bloodshed in Chicago known as the Beer Wars. Over 300 people are murdered at a rate of 75 to 100 murders a year.
Amid the turmoil, Weiss and Moran see an opportunity to take their revenge on Torrio. On January 24, 1925, Weiss and Moran shoot five bullets into Torrio as he walks down a street in broad daylight. Before Weiss can fire a sixth shot – the same amount of bullets that killed O’Banion – the gun jams. He escapes with Moran.
Miraculously, Torrio survives – but he no longer wants to be a part of the business and hands the reins of his empire over to Capone. At the age of 25, Capone is now in charge in the midst of a brutal gangland war.
Preparing for a large-scale battle against his Irish rivals, Capone assembles a team of top lieutenants. Capone puts Frank Nitti, one of his smarter and more violent men, in charge of finances. Paul Ricca, known for his ability to smooth-talk as well as his violent past, becomes his top strategist. Capone brings on brutal killer Tony Accardo to serve as his personal bodyguard and head of enforcement. With his men in place, Capone is ready to take action.
As Capone and his team plan their next move, Weiss and Moran are already prepared to strike. On September 20, 1926, they fire over 200 machine gun bullets into the Hawthorne Inn in the middle of the day. News of the drive-by shooting makes Chicago headlines. Capone tells his men to strike back hard, starting with Weiss.
To take out Weiss, Accardo brings on one of Capone’s top hit men, Jack McGurn. Under orders from Capone, Accardo and McGurn position themselves outside of Weiss’s headquarters at the flower shop. After days of surveillance, they gun down Weiss outside the flower shop.
Capone’s first big hit as a mob boss makes headlines across the country, another example of the escalating gangland violence in Chicago. Instead of keeping a low profile, Capone does the unexpected and calls a press conference at the Hawthorne Inn. He answers questions from journalists and denies his role in Weiss’s murder. He vows to make Chicago a safe place for all.
With Weiss eliminated, what’s left of O’Banion’s organization falls to Moran. He decides to lay low in Irish territory, waiting to plan his next move against Capone.
By wiping out nearly all of his rivals, Capone consolidates his power, controlling more territory than ever before. Now, Capone is determined to return his operations to Chicago and take his rightful place as king of the Chicago underworld.